微生物对食品防腐剂的抗药性研究进展

关于食源性微生物对食品防腐剂的抗药性研究国内未见有详细的研究报导.介绍了食源性微生物对食品防腐剂产生抗药性的研究现状及其应对措施,以期指导食品防腐剂的使用.     

白色及染色PA/EL织物后整理中的泛黄问题

描述了两种用于聚酰胺和聚酰胺／弹性纤维混坊织物的创新工艺——EconBright LG和EconDye LG,这两种新工艺提供了经济的及质量可靠的工艺控制。通过应用Depicol AY和Depicol LC泛黄问题可减小至最少限度。这两种纺织品助剂用于一浴洗涤／染色和后整理工艺中,是Zschimmer ＆ Schwarz Mohsdorf公司开发的。     

AZ 31镁合金化学镀Ni-Cu-Sn-P工艺的研究

通过X射线衍射仪以及极化曲线等手段,优选出最佳化学镀Ni-Cu-Sn-P工艺.结果表明:在硫酸镍30 g/L,硫酸铜0.4 g/L4锡酸钠8 g/L,次磷酸钠18 g/L的条件下,所得Ni-Cu-Sn-P镀层的耐蚀性最好,且为非晶镀层.     

电吸附技术与反渗透技术在市政污水回用处理中的应用

介绍电吸附技术和双膜技术原理及工艺特点,在水源情况相同、回用目的相同、环境影响相同的条件下对比两种水处理技术的优缺点。通过综合考虑项目规模、回用要求、建设用地、资金周转、运行成本等因素,提出选用何种技术,建议将达标污水源、取水设施、输水设施、配套设施等因素也作为参考。     

等离子喷焊镍基合金耐磨性能研究

采用等离子弧喷焊技术在不同转弧电流下喷焊DG.Ni60A和DG.Ni60WC25两种镍基合金粉末,对各喷焊层进行了硬度和耐磨性分析.试验结果表明,转弧电流大小对喷焊镍基合金层的耐磨性影响较大,喷焊DG.Ni60A合金粉末时,转弧电流为100A时的试样磨损量为0.09057g,转弧电流为150A时的试样磨损量高达1.11617g,相差10余倍.喷焊DG.Ni60WC25合金粉末时,转弧电流为100A时的磨损失质量仅为0.01883g,转弧电流为200A时的磨损失质量高达0.74497g,相差约40倍.镍基合金中加入WC,在一定条件下可以提高喷焊层的耐磨性能;转弧电流为150A时,未添加WC硬质相的DG,Ni60A合金粉末喷焊层的磨损失质量高达1.11617g,而添加了WC硬质相的DG.Ni60WC25合金粉末磨损失质量为0.01883～0.74497g.     

铁基堆焊耐磨合金的研究现状

概述耐磨堆焊材料、方法的分类及堆焊层合金元素的性质和堆焊层中碳化物形成特点;对铁基堆焊耐磨合金的固溶强化、第二相强化(弥散强化和析出强化)、晶界强化、热处理和定向凝固等强化方法进行了论述.分析合金元素在堆焊层中的作用、磨料磨损的形貌以及铁基耐磨合金的耐磨机理.铁基堆焊具有成本低、品种多,且易于改变堆焊层强度、韧性、耐磨性、抗冲击性等优点.铁基堆焊耐磨合金是当前研究的重要方向之一,应用前景广阔.     

我国规划建设用地新标准制定的思路探讨

首先分析《城市用地分类与规划建设用地标准(GBJ 137-90)》中“规划建设用地标准”的实施效果及存在的主要问题,然后介绍《城市用地分类与规划建设用地标准(GB 50137-2011)》的研究过程,包括确立“多元控制”的理念以及通过筛选影响要素、引入规划人口规模和气候区划两个因子共同参与人均用地指标的确定,并在现状基础上进行相应的调整.2011版《标准》的“多元控制”方式,可望对各地城市人均用地指标的控制更加具有针对性和灵活性.     

某新建线路大量接地电阻超标原因分析及对策

对福建省某新建220 kV同塔双回线路杆塔接地电阻大量超标的现象进行了分析,得出造成该线路接地电阻大量超标的主要原因是设计不合理,设计人员没有充分考虑各基杆塔的具体情况,仅给出单一的接地形式.在对接地电阻大量超标原因分析的基础上,笔者以某一基杆塔为例,探讨了该杆塔的改造方案,分析表明:该改造方案可起到较好的降阻效果.     

冲江河110kV水电站接地改造分析

对冲江河110kV水电站地网设计不合理,接地电阻严重超标的情况进行了综合分析;通过对该水电站周边地形、地质、土壤电阻率等因素进行了测试和调查之后,结合相关规程及水电站的实际情况提出了通过铺设水下接地网来对水电站接地进行改造的改造方案;计算分析结果表明该方案能够经济有效的解决水电站接地电阻过高的问题.当水下接地网铺设完成后,我们对其接地电阻值进行了测量.最后通对水下接地网接地电阻测量值与计算值的比较,验证了水下接地网解析算法的准确性.     

Probabilistic models for the prediction of target growth interfaces of Listeria monocytogenes on ham and turkey breast products

Abstract: This study developed growth/no growth models for predicting growth boundaries of Listeria monocytogenes on ready‐to‐eat cured ham and uncured turkey breast slices as a function of lactic acid concentration (0% to 4%), dipping time (0 to 4 min), and storage temperature (4 to 10 °C). A 10‐strain composite of L. monocytogenes was inoculated (2 to 3 log CFU/cm²) on slices, followed by dipping into lactic acid and storage in vacuum packages for up to 30 d. Total bacterial (tryptic soy agar plus 0.6% yeast extract) and L. monocytogenes (PALCAM agar) populations were determined on day 0 and at the endpoint of storage. The combinations of parameters that allowed increases in cell counts of L. monocytogenes of at least l log CFU/cm² were assigned the value of 1, while those limiting growth to <1 log CFU/cm² were given the value of 0. The binary data were used in logistic regression analysis for development of models to predict boundaries between growth and no growth of the pathogen at desired probabilities. Indices of model performance and validation with limited available data indicated that the models developed had acceptable goodness of fit. Thus, the described procedures using bacterial growth data from studies with food products may be appropriate in developing growth/no growth models to predict growth and to select lactic acid concentrations and dipping times for control of L. monocytogenes. Practical Application: The models developed in this study may be useful in selecting lactic acid concentrations and dipping times to control growth of Listeria monocytogenes on cured ham and uncured turkey breast during product storage, and in determining probabilities of growth under selected conditions. The modeling procedures followed may also be used for application in model development for other products, conditions, or pathogens.